Fast Fourier Transform and Fast Walsh-Fourier Transform
R. G. Smith, Carleton University, Ottawa, Ontario, Canada
Program l (FFT) computes the 512 point energy density spectra
of two real signals using the Fast Fourier Transform algorithm.
The FFT of a single complex signal may also be computed with
minor modifications to the program. Program 2 (FWFT)
computes the 512 point Fast Walsh-Fourier Transform of a real
signal. Fixed point arithmetic is used throughout both programs
for all computations. A hardware bit-inverter is employed
for speed, and auto-ranging is used to decrease roundoff error.
PDP-8 with EAE, A/D converter
(at least 2 channels), Display
System, External Interrupt and